Various types of scanning laser ophthalmoscopes such as shown in U.S. Pat. Nos. Webb 4,765,730; Webb 4,764,006; Webb 4,768,873 and Kobayashi 4,781,453 are known for scanning a laser that is directed onto the fundus of a patient's eye to allow an interior portion of the eye to be viewed on a display for diagnostic purposes alone.
In order to treat the eye after diagnosis, different devices are currently used. For example, methods for treatment typically employ bright, white light provided by a slit lamp or the like which is shone into the patient's eye. While the eye is thus illuminated, the physician holds a prismatic or focusing contact lens so that it touches the cornea of the patient's eye and then directs a treatment laser through the contact lens. There are several disadvantages associated with this method of treatment. Bright, white light shone into a dilated eye is uncomfortable for the patient. Moreover, when procedures are lengthy, such as a panretinal photocoagulation which can take up to an hour, bright, white light exposure to the retina can approach damaging levels. Further, manipulations of the contact lens, as may be necessary during a procedure, can cause corneal abrasions. Contact of the lens with the eye can also result in the transmission of diseases. Since the contact lens is hand held, unintentional movement can also result in misdirection of the treatment laser.